Stress, by definition is the reaction of an animal body to forces of deleterious nature, infections and various abnormal states that tend to disturb homeostasis.
Animals exposed to stress respond with changes in the activity of the autonomic and neuroendocrine systems and in behavior. The activation of these biological systems is a prerequisite for the animal to cope with stress and thus is the principal resource that will provide the adequate biological defense against a threat that challenges the homeostasis of the animal. Moberg, G.P. Animal Stress, pp. 27-49 (1985); Vogel, W. H. Neuropsychobiology, 13 p. 1290 (1985).
Stress is associated with an objective aggression and the consequences appear in altering different systems such as humoral, metabolic, immunolgic and/or behavioral systems. The hormonal response is traditionally determined by a release of cortisol, a decrease in the secretion of growth hormone and an increase in thyroid hormones and also the sexual steroids. Stress also has a role for diminishing either directly or indirectly the amount of consumption, which is a principal problem with animal breeders. This decrease in the amount of consumption in animals can be caused either by an increase in metabolism or a decrease in food consumption due to stress.
More specifically, stress can be observed by examining several clinical elements in the blood. It is known that in a stressed condition an increase in the ratio of H/L (heterophiles/lymphocytes; heterophiles meaning all white blood cells that are not lymphocytes in avians) and an augmentation in the level of hormones such as circulating T4 (thyroxine), cortisol and prolactin. Davis and Siopas, Poultry Science, 66, pp. 34-43 (1987).
The augmentation of T4 in avians results in the alteration of different well known physiological conditions such as an increase in the level of carbohydrate catabolism, a deregulation of thermoregulation, an increase in heartbeat and an increase in urine and fecal calcium. Idelman, Col. Grenoble Science PUG (1990).
Physiological stressors can also result in an abnormally elevated corticosterone secretion. Campo J .L., S. G. Davila,. Poult. Sci. 81: 1637-1639. (2002); Moberg G. P.,. In: The Biology of animal stress (Moberg & Mench Ed.), CABI, 1-23(2000)
Besides physiological tests, behavioral tests can also be performed to evaluate stress and/or fear in avians. One of the most utilized behavioral tests is the test of Tonic Immobility (TI) as described by Campo J. L., S. G. Davila,. Poult. Sci. 81: 1637-1639 (2002).
It can be appreciated that the change in the physiological conditions due to stress in avians can result, in some instances, in dire effects such as mortality and in many instances loss of weight. Moreover, stress can cause behavioral changes which results in aggressiveness such as pecking other birds, cannibalism, and causing damage to the skin in avian settings. Stress is a real detriment to the aviculturist, since it results in less production of the avian.
Therefore a reduction in stress in birds and especially in avian breeding would lead to less mortality, more weight gain and higher quality production resulting in greater financial gain to the aviculturist.
The advantages resulting from a reduction for in stress in avians are extremely beneficial for those aviculturists who use confinement housing. In confinement housing a large number of avians are raised in cages in hen houses and there are a. large number of birds per cage. Since the avians are confined in a small area with other avians, the stress levels are higher in comparison to those avians that are raised in a free range system. Stress in avians in confinement housing systems can therefore lead to a large loss of yield (Craig J. V., and W. M. Muir, Poult. Sci. 75: 294-302.(1996) due to feather pecking behavior (Kjaer J. B., and P. Sorensen,. Br. Poult. Sci. 38: 333-341 (1997) higher feed to gain ratio (Buitenhuis A. J. et al. 7th WCGALP, Montpellier-France, communication no 14-06) higher mortality (Buitenhuis A .J., et al 7th WCGALP, Montpellier-France, communication no 14-06) or/and poor meat (carcass) quality (Tankston J. D. et al. Poult. Sci. 80: 1384-1389 (2001).
In a confinement housing system, the birds remain indoors and are provided with light twenty-four hours a day to encourage feed consumption. Litter is generally spread on the floor in the hen houses which acts to absorb moisture, dilute manure and provides cushioning and insulation for the birds. In the conventional industry, litter is spread 2 to 4 inches deep and maintained at a 20% to 30% moisture content. There is generally a rest period of about a week between flocks, when the hen houses are cleaned out of de-caked.
By definition, pheromones are substances released by the body that cause a predictable reaction by another individual of the same species.
A number of different glands are known to produce pheromones in male mammals such as the submaxillary salivary glands, the parathyroid glands and the sebaceous glands.
Pheromones that are secreted in submaxillary salivary and parathyroid glands in males, are used to mark females during courtship. In boars, the secretion of these glands results in agnostic behavior. These secretions are known to contain a mixture of androstenol and andosterone.
It is known in the art that pheromones in mammals can be used to reduce stress, anxiety and aggressiveness as demonstrated in U.S. Pat. Nos. 6,077,87, 6,054,481 and 6,169,113. These pheromones were derived from secretions of mammalian mammary glands. However, mammary glands do not exist in birds. Moreover, there are some doubts among specialists about the presence of pheromones in birds since there is no vomeronasal organ, which is a sensory organ with its own pathway to the brain.
The uropygial glands in birds are a bibbed holocrine gland with secretions that form several functions in birds. These functions include waterproofing the feathers, manufacturing of vitamin D precursors, keeping the bill, skin and feathers supple and preventing bacterial infection. The secretions of the uropygial gland are generally spread over the feathers during the act of preening and thus weatherproofs the feathers.
Bohnet et al in the Joumal of Biochemistry vol. 226, No. 15 pp. 9795-9804 (1991) describe the production in female mallards of sex pheromones, diesters of 3-hydroxy fatty acids in their uropygial glands during the mating season. Outside the mating season the uropygial gland only produced a usual monoester wax. It is not known how the uropygial gland switches its biological processes to produce sexual pheromones during the mating season only.
The sexual pheromones as described by Bohnet et al, supra and known to be produced in various birds only during mating season act as attractants or sexual stimulants and cannot be used as appeasing pheromones which act to calm, sooth or relieve anxiety due to stress as in the present invention. Moreover, the chemical composition of sexual pheromones is different than the avian appeasing pheromones of the present invention.
Thus, an aspect of the present invention is to provide an avian appeasing pheromone derived from the uropygial gland of an avian.
In another aspect the present invention provides a composition comprising an avian appeasing pheromone comprising lauric acid, palmitic acid, linoleic acid and oleic acid and/or derivatives thereof and/or isomers thereof, as well as mixtures of one or more of these fatty acids with one or more of their derivatives and/or one or more of their isomers.
In yet another aspect, the present invention provides a composition comprising an avian appeasing pheromone comprising a mixture of about 12.3 to 13.7 (w %/w %) of lauric acid, about 38.0 to 42.0 (w %/w %) palmitic acid, about 32.3 to 35.7 (w %/w % ) linoleic acid and about 12.0 to 14.0 (w %/w %) oleic acid and/or derivatives thereof and/or isomers thereof, as well as mixtures of one or more of these fatty acids with one or more of their derivatives and/or one or more of their isomers.
In yet another aspect the present invention provides a process to treat stress in an avian, said process comprising administering to an avian in need of such treatment an avian appeasing pheromone derived from secretions around the uropygial gland of an avian.
In yet another aspect the present invention relates to a process of treating weight loss in an avian, said process comprising administering to an avian in need of such treatment an avian appeasing pheromonal composition derived from secretions around the uropygial gland of an avian.
In yet still another aspect the present invention provides a process of treating a domestic avian during transportation to eliminate their anxiety, said process comprising administering to an avian in need of such treatment an avian appeasing pheromonal composition derived from secretions around the uropygial gland of an avian.
In another aspect the present invention provides a process to improve feed conversion in an avian comprising administering to an avian in need of such treatment an avian appeasing pheromonal composition derived from secretions around the uropygial gland of an avian.
These and other objects are achieved by the present invention as evidenced by the summary of the invention, description of the preferred embodiments and the claims.